(1S,2R,3R,4R)-α,α,α′,α′-Tetraphenylbicyclo [2.2.1]heptane-2,3-dimethanol and Its Enantiomer as Ligands in Titanate-Complex-Catalyzed Diethylzinc Addition to Aldehydes

Abstract

Starting from (1S,2R,3R,4R)-bicyclo[2.2.1]heptane-2,3-dicarboxylic acid (1) and its enantiomer ent-1 the title compounds 3 and ent-3 were synthesized in 74% yield. They were used in asymmetric synthesis for the first time. The titanate-complex-catalyzed addition of diethylzinc to aldehydes was chosen as a model system for testing the catalytic properties of 3. The resulting alcohols 4 could be obtained with up to 97.7% enantiomeric excess.